#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include<math.h>
int main()
{
	int a = 0;
	int b = 0;
	int c = 0;
	while (scanf("%d%d%d", &a, &b, &c) != EOF)
	{
		if (a + b > c && a + c > b && b + c > a)
		{
			if (a == b && b == c)
			{
				printf("Equilateral triangle!\n");
			}
			else if (a == b || a == c || b == c)
			{
				printf("Isosceles triangle!\n");
			}
			else
			{
				printf("Ordinary triangle!\n");
			}
		}
		else
		{
			printf("Not a triangle!\n");
		}
	}
	return 0;
}